Telephony and Conferencing

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The following sections detail troubleshooting procedures for analog and ISDN modems.

An analog or ISDN modem is not listed

If your modem is not on the Windows 2000 Hardware Compatibility List (HCL) or is not detected by the Install New Hardware or Install New Modem Wizards, use one of the following procedures to install it:

  • Check the modem. If it is an external modem, make sure it is turned on, and all cables are tightly connected. If the modem is internal, verify that it is properly installed.
    If the modem is a Plug and Play device, open Device Manager in Control Panel and select Scan for hardware changes from the Action menu to reinstall the modem. If the modem is a non-Plug and Play device, reinstall the modem using Add/Remove Hardware .

  • Obtain an .inf (installation) file from the modem manufacturer specifically designed for Windows 2000. Follow the manufacturers instructions for installing the modem in Windows 2000, or contact the modem manufacturer for assistance with this procedure.

  • Install your modem as a standard modem using the Install New Modem or Install New Hardware Wizards. This option provides basic dialing and connectivity support for the modem, although manufacturer-specific features might be unavailable.

Phone Dialer cannot dial selected modem

If you cannot use Phone Dialer (or any other application) to dial your modem, verify that Windows 2000 is able to connect to it by testing the modem. In Control Panel, open Phone and Modem Options , and then select the Modems tab, then click Properties for the modem, then select the Diagnostics tab. Click the Query Modem button to send a set of AT commands to the modem. If the modem response is not displayed in the Response area, then perform the following steps to diagnose the problem:

  • If an external modem is experiencing problems, make sure that the serial cable connection between the computer and the modem is secure, and that the cable is not broken or frayed.

  • Verify that Windows 2000 Professional recognizes your COM ports by displaying Device Manager. Verify that the COM port is not experiencing a hardware or resource problem (identified by an exclamation point icon next to the device listing) or has been disabled (the international No symbol). If the connected port is listed without any additional icons, the COM port is recognized and available.

If the COM port is disabled in Device Manager, there is most likely a hardware or a configuration problem. Use the following steps to troubleshoot the problem for an external modem.

  • Verify that the port is not disabled in the BIOS (also called the CMOS) setup of the computer. Refer to the documentation for your computer to obtain information about configuring options in the BIOS setup.

  • Make sure there are no other adapters or devices that are configured for the same base I/O Address or IRQ as the COM port to which the modem is attached.

  • Verify that the serial port is not defective. If the modem and any other serial devices fail on the COM port but work on other COM ports, and you have verified the two steps above, the serial port might be defective.

If the modem experiencing problems is internal, perform the following steps to diagnose and resolve the problem:

  • If the internal modem is not Plug and Play–compatible, it might use jumpers to specify the COM port. Make sure the jumpers on the modem are configured properly. There might or might not be jumpers that allow you to set the base I/O address and IRQ to be used by the modem as well. Verify that they are properly set. Some modems use a configuration application to change these settings.

  • If the modem is configured for a COM port number that is assigned to a COM port on the motherboard or a serial card (physical port), you must either set the modem to use a different COM port, or use the BIOS setup to disable the COM port with the same number as the internal modem.

  • Make sure there are no other adapters or devices that are configured for the same base I/O address or IRQ as the internal modem.

  • Verify that the internal modem is not defective. Also, it is often a good idea to check with the vendor of your modem to see if there is a flash upgrade available for your modem.